<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>01_JS的三种引入方式</title>
</head>
<body>
    <button onclick="alert('请先登录')">点击即玩</button>
    <button onclick="console.log('点我干嘛')">点击即玩2</button>
    <h1 id ="aaa">我是一级标题</h1>
    <script>
        console.log('我是JS单码块')
        console.log(aaa)
    </script>
    <script src="01.js">

    </script>
</body>
</html>